Energy Efficiency Renewable Energy Energy Conservation
The energy it takes to power our buildings—homes, schools, businesses--is an important part of Raleigh’s Community-wide Climate Action Plan (CCAP). For the City, energy is also one of our largest operating expenses. We can improve the impacts of our energy use on climate change by using less energy (conserving energy), reducing the amount of energy it takes to do what we need to do (using energy more efficiently), or reducing the amount of carbon released from the energy we use (using renewable energy).
The City of Raleigh has several energy initiatives. We work on energy conservation, energy efficiency, and renewable energy. We are committed to improving how we use energy and using new energy technologies in order to reduce our greenhouse gas emissions and save money for our residents.
The City applies high standards for energy efficiency for all new municipal buildings and building upgrades. We also test and apply new technologies with the potential to provide energy savings, while maintaining the same level of service and safety for our residents.
Leadership in Energy and Environmental Design (LEED) Buildings
Since 2007, The City of Raleigh has had a policy that new municipal buildings over 10,000 square feet be certified at least at LEED Silver levels. LEED is an internationally recognized certification system for energy efficiency and environmental design. The City will also seek LEED Gold or Platinum Certifications where practical and when funding is available.
We are also prioritizing energy efficiency improvements to existing City buildings. Construction and additions of less thank 10,000 square feet will not necessarily seek LEED Certification, but will be designed to those same standards for energy efficiency.
LEED Certified Municipal Buildings in Raleigh:
- Raleigh Convention Center is one of the first two LEED Silver Certified convention centers in the country.
- Wilder’s Grove Solid Waste Services Center is Certified LEED Platinum
- Raleigh Transit Facility is Certified LEED Platinum
These buildings have more natural light, passive environmental controls and other features that not only conserve energy but also make them more pleasant for occupants and users.
Light Emitting Diodes (LEDs)
Light-emitting diodes are an energy efficient source for lighting both interior and exterior spaces. These lights contains no mercury or other toxic substances as found in other types of lightbulbs. LEDs produce light more efficiently than standard incandescent bulbs, fluorescent lights, and other technologies such as high pressure sodium lamps and metal halide lamps commonly used in outdoor lighting. The bulbs also last up to fifteen years. Since 2006, Raleigh has expanded its use of LED bulbs and the use of this technology saves approximately $215,000 per year in energy and maintenance costs. A few of these projects are detailed below:
- In 2006, Raleigh agreed to become the first LED City, a program that has since expanded across the world. Since then, Raleigh has installed over 40 separate LED projects across the City, including outdoor lighting for City parks, interior lighting, solar LED lighting, streetlights, and lighting in parking decks.
- The LED Streetlight Pilot Project replaced traditional street lighting with high-efficiency LED lights. After a successful pilot, Raleigh began replacing approximately 30,000 conventional lights in fall 2015. It is estimated that LED streetlights operating up to 12 hours a day should last a minimum of 15 to 20 years.
- City Plaza is a showcase of LED lighting, with the four City of Oaks towers, the Art Screens at the southwest and northeast corners of the plaza, and the interactive fountain showing off decorative colored LED lighting, while the bollards and landscape lighting utilize white general lighting.
- Raleigh's leadership in the LED field is dramatically illustrated by the iconic Cree Shimmer Wall adorning the west face of the Raleigh Convention Center.
Renewable energy is clean and naturally occurring. It includes biomass, solar, wind, geothermal, and hydroelectric power. These alternative energies add to Raleigh's energy security and can save the City money over time. In 2016, Raleigh partnered with the North Carolina Sustainable Energy Association on an Renewable Energy Assessment of potential renewable energy technology opportunities in the City’s operations, reduce our dependence on fossil fuels, and provide cost savings.
Solar Photovoltaic (PV) collects the suns rays and turns it into electricity. This process is made possible through the production of free electrons when the solar PV panels are exposed to light. These free electrons are channeled to create an electrical current.
Where is Raleigh using Solar PV?
- Wilders Grove Solid Waste Services Center's main building has a system on its roof and on the truck wash bay . These combined systems produce enough energy to offset approximately 12% of the electrical power needed for the facility.
- EM Johnson Water Treatment Plant has a rooftop solar photovoltaic system, which produces roughly the same amount of energy it takes to power 25 homes in North Carolina for a full year.
- There is a solar array on the roof of Brentwood Operations Center. This project produces the equivalent to the energy use of about six North Carolina homes.
- The City also has several bus stops with solar panels. The renewable energy produced from these solar arrays is used by the City for lighting and message signs at the shelters.
- The Neuse River Wastewater Treatment Plant Solar Farm was designed to generate the equivalent to the annual energy use of about 130 homes in North Carolina every year.
- The Raleigh Convention Center rooftop solar array was completed in June 2012. At the time of its installation, this was the second-largest convention center solar array in the nation, covering approximately 60 percent of the roof. It produces enough energy every year to power about 70 North Carolina homes.
- The City owns a solar array at Annie Louise Wilkerson Nature Preserve Park as an educational resource opportunity.
- BigBelly Solar trash compactors and recycling stations are located on several downtown Raleigh streets and parks. These special waste and recycling stations are powered by solar energy . The power produced by the BigBellys is used to compact the garbage and to signal to the Solid Waste Services Department when they are full.
Solar thermal energy is the process of concentrating sunlight to create high temperatures needed to heat or vaporize fluids, such as water, to drive a turbine for electric power generation.
Where is Raleigh using Solar Thermal?
- In 1983, the City of Raleigh installed a solar thermal system on the roof of the Municipal Building.
- Solar thermal hot water heating systems supplement natural gas units at some of the City's Fire Stations. Installed solar collectors on top of the stations' roofs provide hot water for station needs.
- The solar thermal panels at the Buffaloe Road Aquatic Center help offset the facility's hot water needs. They also work symbiotically with the green roof installation, providing shade for plants.
These solar thermal installations have been an efficient, effective solution to reduce energy consumption.
Geothermal heating and cooling systems use ground temperatures as an energy source for heating and cooling comfort. Though outdoor temperatures fluctuate throughout the year with seasonal changes, ground temperatures four to six feet below the Earth's surface remain relatively moderate and constant year-round.
During the heating cycle, the water circulating through the l system extracts heat from the ground. The geothermal unit compresses the extracted heat to a high temperature and, delivers it to the facility through a heat system. The process is reversed for the cooling cycle. Because the earth is much cooler than the air temperatures on a hot day, the geothermal system removes heat from a business or residence and deposits it into the ground. Also, some of the heat that is removed by the geothermal system can be used to heat water.
This highly efficient way of heating and cooling has been installed at some City of Raleigh facilities.
Where is Raleigh using Geothermal energy?
- The Transit Operations Facility has 150 geothermal wells, each 300 feet deep.
- Wilders Grove Solid Waste Services Center has 60 geothermal wells installed.
The final method the City applies is Energy Conservation. Here again, we rely on technology and design to generate energy and cost savings.
We utilize occupancy sensors and other sophisticated building automation systems to manage energy use in our buildings. This ensures that when staff are not present, we are not unnecessarily using energy. These systems also diagnose problems to prevent energy waste.
As mentioned above, in many municipal buildings we utilize passive solar design such as large windows that allow in natural light and the use of building materials to absorb or deflect solar radiation and use it to limit energy usage within buildings.